HID devices not ready when main.py starts

[dhalbert]

On some hosts (reported on a Windows 10 machine), main.py can start before the HID devices are ready on the host side. Examples:
https://forums.adafruit.com/viewtopic.php?f=52&t=125560#p629406
https://forums.adafruit.com/viewtopic.php?f=52&t=130143
Also reported in Discord (thanks @PhunkMaster)

I added time.sleep(1) to some of the HID examples (e.g., https://learn.adafruit.com/adafruit-circuit-playground-express?view=all#circuitpython-hid-keyboard), but this should really be handled in the library or possibly in the native implementation. The creation operations like Mouse() and Keyboard() could sleep and retry after failure, possibly just once.

[PhunkMaster]

Per @dhalbert 's request, here was the failing code.

import board
import time
import digitalio
import adafruit_dotstar
from adafruit_hid.mouse import Mouse

mouse = Mouse()
led = digitalio.DigitalInOut(board.D13)
led.direction = digitalio.Direction.OUTPUT
led2 = adafruit_dotstar.DotStar(board.APA102_SCK, board.APA102_MOSI, 1)

led2[0] = (129, 0, 250)
while True:
  led.value = False
  led2.brightness = 0.1
  mouse.move(x=1)
  time.sleep(.1)
  mouse.move(y=1)
  time.sleep(.1)
  mouse.move(x=-1)
  time.sleep(.1)
  mouse.move(y=-1)
  led2.brightness = 0.0
  time.sleep(1.0)